Stay-bolt for steam-boilers.



P. M. PATTERSON.

STAY BOLT FOR STEAM BOILERS,

APILIOATION FILED AUG.1, 1908.

91 8, 1 93. I Patented Apr. 13, 1909.

3 AB A v F/G. A H62 3.3 Thefobjectofiriiy int'entionis to? ro' vid'e' a construction ,ofsta bolt whieh s ,11 h 3 :FiBAN-KLIN;M. PATTE BSQN, or HILADELPHIA, ,PENrIsYLvANrA,

, Tdiall whomit concern;

son, a citizen of the United States, "and; av j,.; res denti of-gthe city andicounty :of Philadel" r5 ph1a,-: State of Pa an Improvement in Boilers, of

nnsglvania, have invented if My inirentionflhas' reference to s tay'-bolts 110' for. steam boilers and consistsof certain-i111? provelpentswhich -are fully set forthin the--' o'll'ow ng'. specification-land shown; in the 1 accompanying drawings, which rm1,-a part .great flexibility-9n cheapnessl of construe-j tion while-maintaining-its tensile'strength. i

My invention consists of a steybolt formed 2m asingle .rod'of I metal-having radial inci- .sions''extending from*- the outer surface" .-.wardl-y for-Q artlfofthe radial distance and iorming a so d core with a series of integral. 1 longitudinal outer portions :further, in the e 2 struoture-above specified when twisted upon ongitudinal outer plortions itself so that the.-

' assumefia helical'form-about ais'traig' t' core;

, further, in the construction leststated when -screw jthreaded'-,for v-engagement] with the; .30

construction; which, together with the features above specified, will be better; undenl stood by-refere'nce to-the drawings, which: i Figure 1' is an elevation of thefrod from. which my improved stay-bolt is niade;Fig. 2-

is an end view'of the seine; FigJB'isanele ation-of the same jrod when reduced iDdiMiieter and twisted upon itself; Fig, i is an end View j of the. rod shown in Fig; "3; "Fig. 5 an elevation of m} i111 'rovedstay' bolt applied. to the boiler-sheets efore the ends are u set and. Figgoisan elevation of amodifi'ed orni" of lily-invention; i

- M f 'mproved any suitable manner, but ioreconornyl 'pre fer to make it by thegfollowing method. A

rod o'i-s teel is drawnthroughafsuitable die havin cutting blades which rod uoe'i 1cisions; of V; hape longitudina y of the rod,

portions A integrally connected with .a center Specification or Lettersrate'nte *Beit that I, FRANKLIN Burns 1 tay Bolts for"'Steam j My invention-also, comprehends details of;

stay-bolt may i i 1 so as l'to'form a series of longitudinal-outer Patented s ans, 1909.-

;is hot. Instead of drawing the, bar through a die, it jm'ay'fbe given the incisions B: by .1neansof suitab1e dies employed in a'hydrau {llc orother press. IIt is immaterial to my invention how-the" incisions are made, and while. prefer-to make them stra' lit in "the first operation oi making the stay= o'lt, they 4 ay be .made in helical ,forrn 'apgifro'xirnating" av g V made the rod with the cross section shownin -Fig. 2, Ithen-draw or pass it'through-other "dies to reduceits diameter and close the inf cisions B into the forrn. at E in 4,-

;which thefopposing wallsfofthe parts. A A; contact with each 'other' and. the rod becomes a s'olid rod except for the spaceless incisions. ,E During the operation just described, or as a subsequent independent operation, the rodmay be twisted upon-itself so as to cause the outer portions 1A to take a helical form about. the straight core 0, such helical or .tw'isted io'rmfl being shownin- Fig. .3; With [respect to the pitch-ofthe helical-twist, I do not restrict-InKselL-but I'- prefer that-it shall e full pitch would equal. twice the length of the stay-boltbetween the boilerwhat' is indicatedin Fig; 2.-

be such thatt sheets F, G to be stayed, as indicated in Fig, 151i The, reason for this "willsbe referred to atern Afterthe rod has been brought to the iorin d 85 .4, it is screw threadedifrom one end to the above described and as shown in Figs. 3 an other, as'indicated-atl) in Fig. 5, so that,

' when cutmfiintoproper lengths to form the stay bolts it ma be screwed into, the screw threadedholes in the outer sheet F and This fjoperation' sla be date while themetal g firebox, Sheet Grpreliminary to being upset 'or riveted on its 'ends, as indicated in dotted lines; 1

By dividing the outer the helical form given to the said outer portions.

Furthermore, the; helical twist given to the said outer portions will, in the preferred at. one endto the bottom the other and ortion of the stay bolt into the lon itudinai portionsA, b

consequentlythose fibers which are under tension at one place of their length. are under compression at another, with the result that these .strainscompen'sate and the said fibers forrn, bring the'fibers which are at the top arenas of the parts A are at no time put under 1 integral with the core portion andinwhich rupturing stress; no matter ho: normal strain to whiclrthey p jeoted during commercial use. This action takes lace for of the staybolt in any direction. The stay-bolt may be terupered, if so desired, when in the forms shown in Fig. 3 or Fig. 4. By the employ ment of my invention the usual expansion and contraction of the firebox may take lace Wit out danger of destroying the stay olts.

While Iprefcr to give the helical form to the outer ortions A, nevertheless, under some conditions such helical form may be omitted. In place Of. 111tll1lg,l5ll6 rod in long lengths and cutting it into "the shorter severe the lengths to form. the staybolts, I may maize each stay-bolt separately of the form shown in Fig. 6. In this case the body is of substantially the form above described, but-the ends are solid as the incisions E [do not extend to-the extreme ends of the stay-bolt. These ends are of different diameters and are screw threaded, one end D being larger in diameter than the body portion and the other end D being sinaller. The larger end may-also have a squarepart I or other form for applying a Wrench 01' other tool with "which torotate the stay-bolt when applying it to boiler sheets. In this form of stay-bolt thev bodyart, between the ends, need not be screw t readed. It is also evident that,

by making the rod, shown in Figs. 3 and l, suiiiciently large in diameter, it; maybe turned down to the multiple diameters shown in Fig. 6, and, under such conditions,

be screw threaded on the ends alone.

I have shown my improved stay-bolt in'the form. which I; prefer in commercial practice, but i. do not confine myself thereto the mode of manufacture and the details of construction may be varied Without departing from the spirit of the invention.

Having now described my invention, that I claim as new and. desire tqsecure by Letters latent, is:

l. A stay. bolt formed of a-core portion and a series of radial longitudinal outer per-- tions divided with respect to each other hut integral with the core portion and said series of outer radial portions being closely compacted side by side into a bolt having a con blllllOllS CIOSS SBClZlOIl.

2. A stay-bolt formed of a core portionarranged aboutthe core portion. i

A stay-bolt formed of "a core-portion and a series of radial longitudinal outer portions divided with respectto each other but the .ongitudinalouter portions are helically arranger? about the core. portion and comsolid rod with helically arranged .spaoeless incisions. e. A stay-bolt formed oi ,a core portion and a series of radial longitudinalouter portions divided With respect to each other but integral with the core portion and in which the longitudinal outer portions are helically arran ed about the core portion and screw threaded. for attachment to the boiler sheets; Astay bolt formed of core portion and a seriesof radial longitudinal outer portions' divided with respect to each other but inte ral with the core portion and in which the longitudhial outer portions are helically arranged about the core portion and coinpressed'into close contact so as to form a solid rodwith heliea'lly arranged spaceless incisions and screwthreaded throughout it whole length.- 1

i 5 6. L stay-bolt formedof core portion longitudinal outer portions helically arranged and vinwhich the helical twist is ear-- tended through approximately 180 degrees.

8. p A stay-"bolt provided with screw threads for attachment tothe boiler'sheets and having a body portion. less than its Whole length formed of a core portion surrounded. with a its series of integral longitudinal outer portions helioally arranged and in which the helical twist is extended through approximately 180 degrees. p l 9. The combination of the two sheets F and G of boileig'ivith a stay-bolt H:

having screw threaded portions engagingv thread d holes in said sheets,- and saidstaybolt being formed with a body portion be- ;tween' the sheets made of a core portion surrounded "with a series of longitudinal helical outer portions integral with the core,

the curve of thehelieal portions extendingthrough approximately 180 degrees.

-10. A stay bolt'forined of a core portion and a series of radial longitudinal'outer pore tions in-tegral'witn the core portion and come pacted.v close contact throughout their length side by side, the coreportion and the radialx-longitudinal outer portions being.

each of approximately th u cross tional area. H

11, i. sa bolt having a bodj rsmiea or a core portion and a series of radial'longi amass tudina (mt-er portions dividedwith i'easpeai; in testimony .01? which invention, 1 have ts each; othker, compresseil 911i herew mto stmy hand. u onma 0t 1er mm sac e 11 iniie m it 3 n W1 care portion, said bolt 31;? havi g screww FEM K ERSGN' 5 thzeaded ends, one 0f high of smaflei and Witnesses aha other of which is-of largex diameterthan v R. M. KELLY, the badly pmiom A. W. Rmmm. 

